1. Field of the Invention
The present invention relates generally to a rough-in box for creating penetrations in poured concrete flooring during the construction of high-rise buildings, and a method of using the device.
2. Background
Currently there are a number of solutions for creating penetrations in concrete slab flooring during the construction of high-rise buildings. The penetrations may then be utilized for the installation of plumbing, ducts or other mechanical systems between floors. It has been known to install plumbing or mechanical systems through concrete floors by knocking out holes in the floor or boring such holes after the floor has been formed, and then extending pipes or other conduits through the floors. After the conduits have been inserted into the holes, workers have to pour additional material such as more concrete or caulking material to seal up the spaces between the voids and the conduits extending through the penetrations. However, such attempts to use concrete or caulk to seal up the spaces has not been effective at preventing future problems such as water leaks that travel through any void spaces between the floors. These solutions fail to meet the needs of the industry because they are also time-consuming, labor intensive and wasteful of construction material.
Other solutions include the on-site fabrication of plywood boxes. The boxes are constructed so as to be placed over a roughed-in floor drain area or other location where a floor penetration is desired. The rough-in plywood construction is normally used in order to isolate and protect the rough-in drain at the time of the pouring of a concrete (or cement) floor. But these solutions are similarly unable to meet the needs of the industry because once the flooring is poured the framed openings must be covered with plywood to allow continued construction activity. The plywood creates an uneven floor surface which is a tripping hazard for construction workers and hinders the movement of pallet jacks and other wheeled devices used to deliver construction materials to the needed locations at the site. Furthermore, the wooden frames must be forcibly removed after the concrete is poured, a process which is time consuming and labor intensive.
Other solutions involve the use of metal boxes which are secured to the deck of the floor prior to pouring. This solution has many of the same problems as the use of wooden frames. For example; the metal boxes must be forcibly removed by workers before the concrete is completely cured, creating the need to repair damage to the floor caused by the removal process and the footprints of the workers. When the boxes are removed, the impression hole that is left also needs to be covered to prevent injuries incurred by falling in the hole.
Still other solutions seek to use cylindrical forms or tub-shaped, open-top boxes but these solutions also fail to meet industry needs because they do not provide a flush surface with the flooring. The tubs must be covered with plywood or filled with a foam insert to allow continued construction activity. The cylindrical forms typically protrude above the floor surface creating obstacles. If flush with the floor they must be covered with plywood which creates the problems discussed above.
However, none of the forms described above are suitable for bearing the weight of workers and construction vehicles/equipment/materials while at the same time not creating an uneven floor surface which could be a tripping hazard for construction workers and which could hinder the movement of wheeled devices. Moreover, none of the forms allow construction to continue without the need to remove or trim the forms or covers, such as plywood covers, placed over the forms during the pouring of concrete. There has been no suggestion that the cover to the form should be of a strength that can provide support for both workers and vehicles/equipment/materials that are moving and working on the floor.
With respect to the method of creating penetrations in poured concrete flooring during the construction of high-rise buildings, a typical current construction method using removable metal boxes generally includes the following steps:                (1) The boxes are lifted and placed by crane on the floor that is being readied to be poured.        (2) The boxes are then carried and placed on the prearranged spots on the deck. Depending on the size of the box this may require two workers.        (3) The box is tied to the rebar to prevent the box from being moved or dislodged during the concrete pouring process.        (4) The box is greased to facilitate removal from the concrete.        (5) The concrete is poured to create the slab.        (6) The surface is smoothed to make it flat and level.        (7) To prevent the boxes from becoming stuck in the concrete when it has hardened, when the concrete reaches 75% cure, two workers pry the steel box from the curing concrete. This process damages the surface of the concrete with footprints and also the edges of the hole created by the steel boxes are roughened from the prying action.        (8) The surface of the concrete must be refinished to remove the footprints and other surface damage resulting from removal of the boxes.        (9) During the pouring process, some concrete overflows into the boxes, and when the boxes are removed the hardened concrete has to be removed from the box. This cleaning process requires two workers to strike the box sides with sledgehammers to loosen the concrete and then chip out the remainder with a scraper or chisel.        
(10) The cleaning debris is collected and removed from the floor for disposal.
(11) The cleaned boxes are then stacked, ready to be moved to the next floor.
(12) Before the supports and framing for the next floor can be erected, the open holes have to be covered to prevent injuries. Sheets of plywood are placed over the hole and nailed to the concrete to act as a cover.
This method does not meet the needs of the industry because it has many inherent problems and inefficiencies, some of which are now discussed.
Once the plumbing or mechanical penetrations in one floor are covered, the erection process for the next floor can begin. The support legs for the next floor are put in place and the wooden deck is installed. Due to the presence of the penetrations and wooden covers, the legs sometimes must be placed in different orientations to avoid having the legs being placed on a penetration cover which the leg could potentially puncture. During the erection and pouring process, the wooden penetration covers become dislodged by workers accidentally kicking or knocking the covers loose during the course of working on the erecting floor. Thus, the covers have to be refastened to the floor to prevent workers being injured by stepping into holes.
When a floor is set and ready to be worked on, the stripping and moving of materials and forms can begin on the floor below. This process involves heavy traffic on the floor with the covers in place, and often the covers are dislodged again and must be refastened.
Generally, while the covers are in place, the concrete contractor must maintain the covers for six floors until the general contractor assumes control of the floor to allow the other tradesmen to conduct their work. This maintenance typically consists of daily inspections of the penetration covers on each floor to ensure they are still correctly positioned and fastened to the floor, and refastening loose covers. Once the general contractor takes control of the floor they remove the wooden covers that were covering the penetrations and replace them with a thicker cover that has mitered edges. The old covers then need to be removed from the floor to prevent tripping hazards.
When the plumber or mechanical contractor is ready to begin installing pipes or other conduits in the penetration, it could be almost one month since the slab was poured. Since the holes become roughened from the prying process during removal of the boxes, the holes may need to be adjusted to fit the needs of the particular installation. Once the piping has been completed, the holes need to be filled with concrete to maintain the fire stopping ability of the concrete slab. Due to the fact that this is done at the stage when the units are having the finishing touches applied, it can lead to the some items being scuffed or damaged.
When the mechanical services are ready to run shafts and ducts, they must physically strip the wooden boxes from the cured concrete which is time consuming and also can roughen the sides of the penetration. The penetrations must also he filled with a material to maintain the fire stopping ability.
Suggestions have also been made to provide such cylindrical form or tube with lids to prevent concrete from being poured into the forms. Such forms are described, for example, in U.S. Patent Publication 2005/0055916 describing a plasticized form which is used to surround plumbing fixtures while concrete is being poured and has a lid secured to the form that provides an intermediate covering to the form assembly and until such time as the plumber completes the connection, U.S. Pat. No. 7,080,486 describes including intumescent material in a leave in place form which may be provided with a cap, the form being provided with frangible bands to allow adjustment of the form to the thickness of the floor. The cap is stated to be used to prevent concrete from being poured into the form. U.S. Pat. No. 4,823,527 describes a hollow form having a cover that can be coplanar with the top surface of a concrete floor and means for adjusting the height at which this form is located above the floor support. U.S. Pat. No. 4,077,599 describes an aperture-forming device for making openings, for example tubular openings in concrete. U.S. Pat. No. 7,073,766 describes a form work having a moveable outer frame linked to an inner rigid frame thereby permitting adjustment of its size. U.S. Pat. No. 4,666,388 describes a form for forming an opening such as a window or door which is adapted to collapse inwardly after use.
It would be desirable to have a device and method of using the device that can be used to retain an opening in concrete slab flooring during the pouring of the concrete which is capable of providing an upper surface flush with the concrete floor, has the structural strength to support the weight of workers and construction supplies, can remain in in place after construction and has waterproofing and fireproofing capabilities. This would eliminate the need to cover openings with plywood, which creates a tripping hazard for construction workers and impedes the movement of wheeled carts and trucks which are used to move materials around the construction site. Still further, it would be desirable to have a device that provides a waterproof and fireproof barrier. Still further, it would be desirable to have a device and method that provides for improved efficiency, increased safety, and reduced labor costs. Therefore, there currently exists a need in the industry for a device and associated method that provides for an opening in poured concrete flooring, with an upper surface which is flush with the surrounding floor, strong enough to support the weight of construction materials and workers, waterproof, fireproof, and cost effective. Therefore, there currently exists a need in the industry for a device and method of use that solves all the problems addressed above.
Specifically there is a need for a form that can be used to enable penetrations to be left in a concrete floor while concrete for the floor is being poured, that can permit work on the floor to continue without the need for removal of materials, that provides a. fireproof and waterproof barrier and desirably can easily accommodate different sized penetrations.